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71.
The ecological structure of Paleozoic ammonoid assemblages of the Uralian paleobasin is discussed. Life forms (nektobenthic, planktonic, and benthopelagic) are used as ecological units. Four stages in evolution of the communities, with distinct structure and evolutionary pathways, are recognized.  相似文献   
72.
The Upper Viséan–Serpukhovian ammonoid-rich carbonates in the Dombar Hills (Aktobe Region, western Kazakhstan) provide an excellent opportunity to calibrate the ammonoid and conodont zonations around the base of the Serpukhovian Stage, and are important for interregional correlation. A section in the Dombar Hills spanning the Viséan–Serpukhovian boundary is measured and its fossil content is analyzed. Two ammonoid genozones (Hypergoniatites-Ferganoceras and Uralopronorites-Cravenoceras) and two conodont zones (Lochriea nodosa and Lochriea ziegleri) are recognized. The section displays a contact between the Hypergoniatites-Ferganoceras and Uralopronorites-Cravenoceras ammonoid genozones in a continuous succession and an evolutionarily early appearance of the genus Cravenoceras. The base of the Serpukhovian Stage is drawn at the level of the first appearance datum (FAD) of the conodont Lochriea ziegleri, which, as in the Verkhnyaya Kardailovka section (potential GSSP candidate, South Urals, Russia) enters within the Hypergoniatites-Ferganoceras ammonoid Genozone.  相似文献   
73.
The review describes the latest data on the role of antimicrobial peptides (AMPs) in health and disease, as well as their structure and mechanisms of action. AMPs mediate protection by both direct lysis of bacteria and also by regulation of inflammation and chemotaxis, thus demonstrating immunomodulatory properties. A large amount of data shows that AMPs play an important role in the pathogenesis of multiple chronic diseases with genetic predisposition, such as atopic dermatitis, rosacea, and scleroderma.  相似文献   
74.
Dmitrenko  G. N.  Konovalova  V. V.  Shum  O. A. 《Microbiology》2003,72(3):327-330
Non-nitrate-reducing collection bacteria from the genus Pseudomonas were found to be able to use hexavalent chromium as a terminal electron acceptor. The reduction of Cr(VI) was accompanied by an increase in the cell biomass. At Cr(VI) concentrations in the medium lower than 15 mg/l, the non-nitrate-reducing pseudomonads reduced Cr(VI) less efficiently than did denitrifying pseudomonads. In contrast, at Cr(VI) concentrations higher than 30 mg/l, Cr(VI) was reduced more efficiently by the non-nitrate-reducing pseudomonads than by the denitrifying pseudomonads.  相似文献   
75.
The genes that were induced and suppressed in human embryonic kidney cell line RH upon the infection with tick-borne encephalitis virus were studied by the method of subtractive hybridization. The expression of interferon-induced genes IFI-54K and IFI-56K in the infected cells was found to increase 50–100-fold.  相似文献   
76.
Introduction. Huntington’s disease (HD) is a severe neurodegenerative disorder characterized by choreic hyperkinesis, cognitive decline, behavioral disorders, and progressive neuronal death, mostly in the striatum. Since HD is a fatal disorder, searching for efficient treatment methods, including those based on cell replacement therapy, is quite relevant. The experimental models of HD are used increasingly often. The objective of the study was to assess effectiveness and safety of transplantation of neuronal precursors differentiated from induced pluripotent stem cells (iPSCs) from a healthy donor into the striatum of rats with 3-NPAinduced HD model. Materials and methods. We studied the influence of neurotransplantation on the behavioral effects in rats with HD model induced by intrastriatal injection of 3-nitropropiotic acid (3-NPA). In the study group of animals (n = 11), human neuronal precursors derived from iPSCs of a healthy volunteer were transplanted into the caudate nuclei (5 × 105 per 5 μL of normal saline solution bilaterally); the control group of animals (n = 10) received normal saline solution. The animals were tested using the ANY-maze video tracking system; the parameters of the open-field test and the conditioned avoidance response test were evaluated. Results. An analysis of behavioral effects after transplantation demonstrated that introduction of neuronal iPSC derivatives into the caudate nuclei of rats with induced HD model was accompanied by recovery of locomotor activity of the animals (horizontal and vertical), as opposed to the control group. It was found when testing the reproducibility of the conditioned avoidance responses that the conditioned avoidance responses in control animals were weakened, whereas intrastriatal transplantation of neurons abruptly increased the latency of moving into the dark compartment of the chamber in the conditioned avoidance response test. Conclusions. The pilot experiment using the HD model showed that neurotransplantation using iPSC derivatives recovers the reduced locomotor activity in rats and improves memory trace keeping, which contributes to correction of locomotor and cognitive disorders induced by 3-NPA neurotoxin.  相似文献   
77.
The data obtained in the clinical and laboratory study of 72 hospitalized patients with acute enteric infection are presented. The observed outbreak was caused by H. alvei producing heat-stable enterotoxin. The role of this etiological agent is also confirmed by simultaneous occurrence of the disease after using the same foodstuff, a short incubation period, the severity of the course of the disease with pronounced symptoms of neurotoxicosis, a high detection rate of H. alvei in material taken from patients at the acute period of the disease, rapid disappearance of this agent in the period of convalescence and a pronounced rise in the titer of specific antibodies to H. alvei in the dynamics of the disease. At the same time in the feces of 8 patients rotavirus antigen was detected, which, in combination with residual catarrhal phenomena, hyperemia and granularity of the pharynx, yellow stool, was indicative of the simultaneous circulation of rotavirus among these patients.  相似文献   
78.
The genes that were induced and suppressed in human embryonic kidney cell line RH upon the infection with tick-borne encephalitis virus were studied by the method of subtractive hybridization. The expression of interferon-induced genes IFI-54K and IFI-56K in the infected cells was found to increase 50-100-fold.  相似文献   
79.
The aim of our research was to study the apoptotic index and the representativeness of CD95-receptor in the effector cells, in addition to estimation of the content of tumor necrosis factor-alpha in the induced sputum supernatant observed in patients with bronchial asthma and chronic obstructive bronchitis. These indices were evaluated in the disease dynamics and involves various treatment programs. The object of our research was induced sputum. The analysis has proven that apoptotic index of effector cell nuclei, representativeness of CD95-receptor and the content of tumor necrosis factor-alpha in the induced sputum differed, respectively, in patients with bronchial asthma and chronical obstructive bronchitis, and depended on the period of disease and employed treatment. The induced sputum analysis results can be used for the airway inflammation activity monitoring, with regard to these diseases and to treatment efficiency monitoring.  相似文献   
80.
Diporphyrin systems based on tetraphenylporphyrin derivatives bridged with dipeptide or tripeptide spacers containing Gly and Phe residues were synthesized, and their physicochemical properties were studied.  相似文献   
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